KR20090117970A - Mat materials, method for producing mat materials, silencer and method for producing silencer - Google Patents

Abstract

A mat material that even when disposed in high-temperature conditions in the use in automobile muffler, etc., can be free from breakage due to wind erosion and thermal deterioration and excels in handleability. The mat material has the following characteristics. The mat material is composed mainly of an inorganic fiber. The mat material has multiple needle vestiges each provided by needle punching running from a needle penetration vestige provided on one surface to a needle departure vestige provided on the surface opposite to the surface provided with the needle penetration vestige. The needle departure vestige is provided with an inorganic fiber hank resulting from orientation of multiple inorganic fibers into a closed-loop configuration. The inorganic fiber hank is provided on at least one of the surfaces.

Description

MAT MATERIALS, METHOD FOR PRODUCING MAT MATERIALS, SILENCER AND METHOD FOR PRODUCING SILENCER}

TECHNICAL FIELD This invention relates to a mat material, a manufacturing method of a mat material, a silencer, and a manufacturing method of a silencer.

Background Art In a conventional internal combustion engine such as a motor vehicle, it is known that noise is generated as exhaust gas generated from an internal combustion engine is discharged to the outside through an exhaust path.

Therefore, various kinds of silencers provided in the exhaust path are proposed for the purpose of damping noise.

In particular, for the purpose of attenuating noise in the high frequency region, an inner pipe having a mat member made of inorganic fibers or the like, a plurality of small pores in which the mat member is wound, and an outside where the mat member and the inner pipe are disposed therein Pipe silencers are used.

In such a muffler, generally, the exhaust gas discharged from the internal combustion engine flows into the inner pipe from the inlet side of the inner pipe through the exhaust path. The exhaust gas passing through the inner pipe is discharged to the outside from the outlet side of the inner pipe. At this time, the noise in the high frequency region is absorbed and diffused by the plurality of small pores formed in the inner pipe and the mat member surrounding the small pores. By employing such a silencer, it is possible to attenuate the noise, particularly in the high frequency region.

As a mat material used for such a silencer, the mat material using the crystalline alumina fiber which controlled the crystallization rate is disclosed (patent document 1).

Patent Document 1: Japanese Unexamined Patent Publication No. 2006-022817

The mat member described in Patent Document 1 has a certain effect of damping noise. However, when such a mat member is used in a silencer, peeling of inorganic fibers near the mat member surface due to stress accompanying the flow of exhaust gas, that is, Winding occurs, and finally the mat member is damaged. As a result, there is a problem that the effect of damping noise is reduced or the appearance of the outer pipe is damaged. This is considered to be because the interlayer strength is not high enough in the mat member described in Patent Document 1.

Moreover, when manufacturing a silencer using the mat material of patent document 1, it is difficult to press-fit the inner pipe by which the mat material was wound to the outer pipe, and also there exists a problem that handleability is inferior.

Therefore, even when used for the silencer of an automobile, the mat | matte material excellent in handleability was desired while being able to prevent damage by wind and wind.

The present invention has been made to solve the above problems, and for example, even when used in a silencer of an automobile, an object of the present invention is to provide a mat member having excellent handleability while preventing damage caused by wind. will be.

The mat member of Claim 1 contains an inorganic fiber, and needle punching advances from the needle penetration trace formed in the surface to the needle penetration trace formed in the surface opposite to the surface in which the said needle penetration trace was formed. A plurality of needle traces formed by the treatment are formed, and in the needle bleed traces, an inorganic fiber bundle in which the plurality of inorganic fibers are oriented in a closed loop shape is formed, and the inorganic fiber bundle is formed on at least one surface. It is characterized by being formed.

According to the mat member according to claim 1, the mat member has a plurality of needle traces formed by a needle punching process that advances from the needle penetration trace formed on the surface to the needle penetration trace formed on the surface opposite to the surface on which the needle penetration trace is formed. have. That is, in the said mat material, entanglement of an inorganic fiber generate | occur | produces in the needle trace and the needle trace vicinity all over the thickness direction of a mat material, and the interlayer strength of the whole mat material is high. Therefore, when the mat material of Claim 1 which has such a structure is used for a silencer, an inorganic fiber does not peel easily by the stress accompanying the flow of exhaust gas, and the damage of the whole mat material by wind-weather can be prevented. Can be.

Therefore, the effect of damping noise can be maintained for a long time.

In addition, since the heat insulating property of the mat member is not impaired well, it is possible to prevent the temperature rise of the outer pipe. Furthermore, discoloration by the heat of an outer pipe can be prevented. Therefore, it can be set as the mat member which does not damage the external pipe appearance well.

In addition, in this specification, needle punching process forms the sheet-like thing by penetrating a some needle toward the other surface from one surface of the sheet-like thing which becomes a mat material after baking, and the inorganic fiber which becomes an inorganic fiber after baking It refers to the treatment which makes the precursors entangled with each other, that is, the treatment which entangles the inorganic fiber precursor.

By firing the sheet-like article subjected to such needle punching treatment, the organic polymer contained in the inorganic fiber precursor is decomposed and lost to obtain a mat member in which the entanglement of the inorganic fibers has occurred.

In addition, the interlaminar strength refers to the maximum stress at which the mat member can maintain its original shape when a load is applied to the mat member by an operation such as pulling or tearing.

The correlation between this interlaminar strength and the entanglement of the inorganic fibers in the mat material is such that the greater the degree of entanglement of the inorganic fibers in the mat material and the greater the number of entanglements of the inorganic fibers, the higher the interlayer strength of the entire mat material is. .

The reason why the mat member according to claim 1 can exert the above-described effects will be described below with reference to the drawings.

1: (a) is a partially cutaway perspective view which shows typically the mat material containing the cross section obtained when the example of the mat material of Claim 1 is cut | disconnected along the thickness direction.

The mat member 10 of Claim 1 consists mainly of inorganic fibers, and the external shape is flat shape which is substantially rectangular in plan view, and has predetermined thickness. The external shape of the mat member 10 of Claim 1 is demonstrated in description of 1st Embodiment mentioned later, and the detailed structure of the surface and the inside of the mat member 10 of Claim 1 is demonstrated below.

As shown to Fig.1 (a), in the surface 13a of the mat material 10 of Claim 1, the needle penetration mark 14 is formed in the point which the needle penetrated by performing the needle punching process mentioned above. have. In addition, in the surface 13b on which the needle penetration mark 14 was formed, the needle penetration mark 15 is formed at the point where the needle was inserted (the point corresponding to the needle penetration mark 14). . And inside the mat member 10, a plurality of needle traces 16 are formed which are advanced from the needle penetration trace 14 to the needle extraction trace 15, and the needle trace 16 and the vicinity of the needle trace 17 are formed. In this case, entanglement of inorganic fibers has occurred.

It is considered that entanglement of the inorganic fibers in the needle trace and the needle trace vicinity occurs for the following reason.

Here, as a needle used for the needle punching process, a case in which a needle having a plurality of visible projections (barbs) protruding toward the tip direction (penetration direction) over the entire circumference of the side of the tip portion is used. An example will be described.

When the needle punching process is performed with respect to the sheet-like thing which consists of inorganic fiber precursors using the needle mentioned above, a needle penetrates into the surface of a sheet-like thing first. The needle proceeds in the inorganic fiber precursor while barb generates an entanglement in the inorganic fiber precursor near the needle by drawing the inorganic fiber precursor near the needle in the direction of travel of the needle. Thereafter, the needle is pulled out, and since the barb is formed in a direction opposite to that in which the needle is pulled out, the inorganic fiber precursor is not attracted to the barb again. Therefore, entanglement of the inorganic fiber precursor occurs in the needle trace and the needle trace formed after the needle is pulled out. Accordingly, by firing this sheet-like article, a mat material having an needle fiber and an interweave of inorganic fibers in the vicinity of the needle trace is obtained.

Thus, in the mat material 10 of Claim 1, since the inorganic fiber is entangled in the needle trace 16 and the needle trace vicinity 17 over the whole thickness direction of the mat material 10, needle punching process is performed. The interlayer strength of the whole mat material 10 is high compared with the mat material which was not implemented.

Therefore, when the mat material of Claim 1 is used for a silencer, inorganic fiber rarely peels off by the stress accompanying the flow of exhaust gas, and damage to a mat material by wind-weather can be prevented.

In addition, as shown to Fig.1 (a), in the some needle bleed trace 15 formed in the surface 13b of the mat material 10 of Claim 1, many inorganic fibers which comprise the mat material 10 are many. Inorganic fiber bundle 18 is formed by being bundled together. And the direction of each inorganic fiber which comprises the inorganic fiber bundle 18 is arrange | positioned in a fixed direction so that the shape of this inorganic fiber bundle 18 may form a loop (Hereafter, the direction of an inorganic fiber is fixed direction). Roughly aligned). Moreover, since both ends of the inorganic fiber bundle 18 couple | bond with a mat material, it becomes a loop shape (henceforth a closed loop form) with both ends closed.

Thus, in the mat member 10 of Claim 1, each inorganic fiber which comprises the inorganic fiber bundle 18 is orientated in the closed loop shape, and there is little fluff of an inorganic fiber. Therefore, for example, when manufacturing a silencer using the mat material of Claim 1, since the inorganic fiber which comprises the inorganic fiber bundle 18 hardly sticks to an operator's skin, it has high stability for an operator. I can do it with mat material.

Moreover, as a shape of the inorganic fiber bundle 18, if it is a closed loop shape mentioned above, it will not specifically limit, The shape shown to FIG. 1 (b) is mentioned. FIG.1 (b) is a perspective view which shows typically the inorganic fiber bundle formed in the surface 13b of the mat material 10 shown to FIG.1 (a).

As shown in FIG. 1 (b), as the shape of the inorganic fiber bundle 18, for example, the shape in which the inorganic fiber bundle 18 oriented in a closed loop shape is horizontally laid on the surface of the mat member 10 ( 18a), the shape in which the inorganic fiber bundle 18 oriented in the closed loop shape is twisted and crossed, the shape in which the inorganic fiber bundle 18 oriented in the closed loop shape protrudes from the surface of the mat member 10 ( 18c), the shape 18d in which a part of the inorganic fiber bundle 18 oriented in the closed loop form a small loop, and the inorganic fiber bundle 18 oriented in the closed loop form the The shape 18e etc. which protrude slightly from the surface are mentioned.

In the mat member according to claim 1, the reason why the inorganic fiber bundle 18 is formed is considered as follows.

In the needle punching treatment described above, the needle advances inside the mat member 10 in a state where a plurality of inorganic fiber precursors drawn into the barb are entangled with the barb. In this process, the inorganic fiber precursor is oriented in a loop shape along the barb formed over approximately the entire circumference of the side of the needle tip portion (hereinafter, the inorganic fiber precursor oriented in the loop shape is also called a bundle-shaped inorganic fiber precursor). ). Then, the needle is ejected to the surface opposite to the side on which the needle of the sheet-like product is penetrated, so that most of the bundle-shaped inorganic fiber precursors are pushed out from the needle ejection marks. Thereafter, the needle is pulled out. Since the barb protrudes in a direction opposite to the direction in which the needle is pulled out, the bundle-shaped inorganic fiber precursor is not attracted to the barb again. Therefore, the bundle-shaped inorganic fiber precursor which is oriented in the closed loop shape stays on the needle outflow trace of the surface of the sheet-like object. Therefore, by baking this sheet-like object, the mat material in which the inorganic fiber bundle which is orientated in the closed loop shape in the needle outflow trace of the mat material surface is obtained.

Moreover, the inorganic fiber bundle may be formed in all the needle outflow traces, and may be formed in some needle outflow traces.

In the mat member 10 according to claim 1, fine irregularities are formed on the mat member 10 surface 13b by the inorganic fiber bundle 18 formed on the surface 13b of the mat member 10. Since the contact area at the time of contacting with the surface of another object becomes small by this fine unevenness | corrugation, the friction coefficient of the surface 13b of the mat material 10 becomes small compared with the surface of the mat material in which the inorganic fiber bundle is not formed. have.

Therefore, for example, when manufacturing a silencer using this mat material 10, the mat 13 (outside) is arrange | positioned so that the surface 13b of the mat material 10 may be arrange | positioned at the outer pipe side (outer side). After winding 10), by pressing this inner pipe into the outer pipe, the frictional force between the surface 13b of the mat member 10 on which the inorganic fiber bundle 18 is formed and the inner surface of the outer pipe can be reduced.

Therefore, when manufacturing a silencer using the mat material of Claim 1, since the inner pipe by which the mat material was wound can be easily press-fitted into an outer pipe, it can be set as the mat material excellent in handleability.

As described in detail above, when the mat material according to claim 1 is used for the silencer, the strength of the entire layer of the mat material is high, so that the inorganic fibers are less likely to be peeled off due to the stress accompanying the flow of the exhaust gas. The damage of the mat material by this can be prevented. Therefore, the effect of damping noise can be maintained for a long time.

And when manufacturing a silencer using the mat material of Claim 1, since the inner pipe by which the mat material was wound can be easily press-fitted to an outer pipe, it can be set as the mat material excellent in handleability.

In addition, in this specification, the mat material containing an inorganic fiber shall mean the mat material containing 60 weight% or more, Preferably it is 80 weight% or more of inorganic fiber. In addition, the mat material may contain, for example, an organic binder, an inorganic binder, an organic fiber, an organic film, a metal fiber, vermiculite, or the like, in addition to the inorganic fiber. When the said organic binder etc. are contained other than an inorganic fiber, the inorganic fibers which comprise a mat material can be mutually adhere | attached as described in the mat material of Claim 7 mentioned later. Therefore, an inorganic fiber does not fall off from a mat material well.

In the mat member according to claim 2, the needle needle is a first needle trace which is advanced from the first needle penetration trace formed on the first surface of the mat member to the first needle penetration trace formed on the second surface,

And a second needle mark which extends from the second needle penetration mark formed on the second surface of the mat member to the second needle penetration mark formed on the first surface.

In the mat member of Claim 2, the advancing direction of the said 1st needle trace and the said 2nd needle trace opposes each other. That is, in the vicinity of the first needle trace and in the vicinity of the second needle trace, the directions of entanglement of the inorganic fibers are different from each other, and the inorganic fibers are more entangled with each other in the mat material.

Therefore, in the mat | matte material of Claim 2, the interlayer intensity | strength becomes high throughout the whole thickness direction of a mat material.

Therefore, when the mat material of Claim 2 is used for a silencer, the effect of Claim 1 can be exhibited, and since inorganic fiber is less likely to be peeled off by the stress accompanying the flow of exhaust gas, it is necessary The damage of the mat material by this can be prevented more efficiently.

In the mat member of Claim 3, the formation density of the 2nd inorganic fiber bundle formed in the said 1st surface differs from the formation density of the 1st inorganic fiber bundle formed in the said 2nd surface.

Here, the strength of the portion containing the inorganic fiber bundle on the surface of the mat member is considered to be lower than the strength of the portion where the inorganic fiber bundle is not formed. Therefore, when the mat material is used for the silencer, the part containing the inorganic fiber bundle on the surface of the mat material is exposed from the small holes of the inner pipe and is exposed to the stress accompanying the flow of the exhaust gas. It is thought that this may occur. Therefore, in order to prevent damage to the surface of the mat member due to wind, it is preferable that the inorganic fiber bundle is not formed on the surface of the mat member disposed on the inner pipe side (inner side).

On the other hand, in order to more effectively prevent the occurrence of breakage of the entire mat material due to the wind, it is preferable to form the first needle trace and the second needle trace different from each other in the advancing direction to increase the interlayer strength of the entire mat member. desirable. In this state, the inorganic fiber bundle is formed on both the first and second surfaces of the mat member.

The mat material of Claim 3 has achieved the opposing objective mentioned above by having the 1st surface and 2nd surface from which the density of inorganic fiber bundles mutually differ.

That is, when the mat material of Claim 3 is used for a silencer, the inner pipe is arrange | positioned by arrange | positioning the surface with many inorganic fiber bundles to the outer pipe side (outer side), and arrange | positioning the surface with few inorganic fiber bundles to the inner pipe side (inner side). The interlayer strength of the whole mat material can be made higher, suppressing the peeling of the inorganic fiber of the mat material surface to the minimum on the surface of the mat material arrange | positioned at the side. Therefore, the damage of the whole mat material by wind can be prevented more efficiently.

In the mat member of Claim 4, the average fiber diameter of the said inorganic fiber is 3-10 micrometers.

Here, when the average fiber diameter of the said inorganic fiber is 3-10 micrometers, since the intensity | strength of the inorganic fiber itself can be ensured enough, the interlayer strength of the whole mat material can be made high.

On the contrary, when the average fiber diameter of the said inorganic fiber is less than 3 micrometers, the intensity | strength of the inorganic fiber itself may fall, and the interlayer strength of the whole mat material may fall.

Moreover, when the average fiber diameter of the said inorganic fiber exceeds 10 micrometers, the surface area of the said inorganic fiber may become small, and may cause the fall of the sound absorption characteristic of a mat material. In addition, since the number of inorganic fibers constituting the mat member per unit volume is small, the number of the inorganic fibers entangled with each other in the vicinity of the needle trace and the needle trace may be low, and the interlayer strength of the entire mat member may be lowered.

According to the mat member of Claim 4, since the average fiber diameter of the said inorganic fiber is in the said range, it can be set as the mat member with higher interlayer strength of the whole.

Therefore, when the mat material of Claim 4 is used for a silencer, the effect of Claim 1 can be exhibited, and since inorganic fiber is less likely to be peeled off by the stress accompanying the flow of exhaust gas, The damage of the mat material by this can be prevented more efficiently.

In the mat member of Claim 5, the formation density of the said needle trace is 7-30 pieces / cm <2>.

When the formation density of needle traces is 7-30 pieces / cm <2>, since the needle traces formed per unit area can fully be secured, the interlayer strength of the whole mat material can be made high. In addition, since the inorganic fiber bundle formed on the surface of the mat member is sufficiently secured, the coefficient of friction of the surface of the mat member on which the inorganic fiber bundle is formed is small. Therefore, when the inner pipe wound with the mat member is pressed into the outer pipe, the friction force between the surface of the mat member and the inner surface of the outer pipe can be reduced.

In addition, in the needle punching process, since the inorganic fiber precursor becomes difficult to be finely cut, the strength of the inorganic fiber itself can be sufficiently secured. Therefore, the interlayer strength of the whole mat material can be made high.

On the contrary, when the formation density of the needle traces is less than 7 / cm 2, the needle traces formed per unit area decreases, and the interlayer strength of the entire mat material may be lowered. In addition, there may be less inorganic fiber bundles formed on the surface of the mat material, so that the coefficient of friction on the surface of the mat material on which the inorganic fiber bundle is formed may increase.

Moreover, when the formation density of a needle trace exceeds 30 pieces / cm <2>, an inorganic fiber precursor may be finely cut and the intensity | strength of the inorganic fiber itself may fall.

According to the mat member of Claim 5, since the formation density of the said needle trace is in the said range, it can be set as the mat member with very high interlayer strength of the whole.

Therefore, when the mat material of Claim 5 is used for a silencer, the effect of Claim 1 can be exhibited, and since inorganic fiber rarely peels off by the stress accompanying the flow of exhaust gas, It is possible to prevent damage to the mat member very efficiently. In addition, since the formation density of the said needle trace is the said range, when manufacturing the silencer using the mat material of Claim 5, the mat material of Claim 5 reduces the friction force between the surface of a mat material and the inner surface of an outer pipe. It can reduce more. Therefore, since the inner pipe in which the mat material is wound can be press-fitted to the outer pipe more easily, the mat material can be made more excellent in handleability.

In the mat member according to claim 6, the inorganic fiber is an inorganic fiber containing at least one of alumina and silica.

According to the mat member according to claim 6, the inorganic fibers constituting the mat member are inorganic fibers containing at least one of alumina and silica, and are excellent in heat resistance.

Therefore, even when the silencer using the mat material of Claim 6 is installed in an exhaust path, an inorganic fiber does not melt | dissolve easily. Therefore, even if, for example, the distance between the internal combustion engine and the silencer is short, such as a two-wheeled vehicle, and the exhaust gas has a high temperature of about 800 to 850 ° C, the effect of damping the noise can be maintained for a longer time. .

In the mat member according to claim 7, the mat portion contains an organic binder.

According to the mat member of claim 7, the inorganic fibers constituting the mat member are adhered to each other by an organic binder, so that the inorganic fibers constituting the mat member are hardly eliminated. Therefore, when manufacturing a silencer using the mat material of Claim 7, even if processing, such as winding a mat material with respect to an internal pipe, the fall of an inorganic fiber does not occur easily, and the dropped inorganic fiber is the thing of an operator. Since there is little incidence of sticking to the skin or inhaling the scattered inorganic fibers, it is possible to provide a highly stable mat member for the worker.

The manufacturing method of the mat material of Claim 8 is a spinning process which spins the spinning mixture containing an inorganic compound and an organic polymer at least, and manufactures an inorganic fiber precursor,

A compression step of compressing the inorganic fiber precursor to produce a sheet-like article;

Needle punching which produces the needle punching process body in which the inorganic fiber bundle in which the said inorganic fiber precursor is orientated in the closed loop form on the at least one surface of the said sheet-like thing is performed by performing a needle punching process on the at least one surface of the said sheet-like thing. Fair,

The mat material containing inorganic fiber is produced by performing the baking process which bakes the said needle punching process object.

In the manufacturing method of the mat material of Claim 8, the mat material of Claim 1 can be manufactured suitably by performing the above-mentioned process.

In the manufacturing method of the mat material of Claim 9, the said needle punching process is given to both surfaces of the said sheet-like thing.

In the manufacturing method of the mat material of Claim 9, the mat material of Claim 2 can be manufactured suitably by performing the above-mentioned process.

In the manufacturing method of the mat member of Claim 10, the needle punching process is performed by changing the number of the needles which penetrate into the said sheet-like thing in one surface and the other surface of the said sheet-like thing.

In the manufacturing method of the mat material of Claim 10, the mat material of Claim 3 can be manufactured suitably by implementing the above-mentioned process.

In the manufacturing method of the mat member of Claim 11, the said needle punching process is performed by changing the frequency | count which introduces a needle into the said sheet-like thing in the one surface side and the other surface side of the said sheet-like thing.

Also by the manufacturing method of the mat material of Claim 11, the mat material of Claim 3 can be manufactured suitably by implementing the above-mentioned process.

In the manufacturing method of the mat material of Claim 12, the average fiber diameter of the inorganic fiber which comprises the said mat material is 3-10 micrometers.

According to the manufacturing method of the mat material of Claim 12, the mat material of Claim 4 can be manufactured suitably by implementing the above-mentioned process.

In the manufacturing method of the mat member of Claim 13, the formation density of the needle trace formed by the said needle punching process is 7-30 pieces / cm <2>.

According to the manufacturing method of the mat material of Claim 13, the mat material of Claim 5 can be manufactured suitably by implementing the above-mentioned process.

In the manufacturing method of the mat member of Claim 14, the said inorganic compound contains at least one of the inorganic compound which turns into alumina after baking, and the inorganic compound which turns into silica after baking.

According to the manufacturing method of the mat material of Claim 14, the mat material of Claim 6 can be manufactured suitably by implementing the above-mentioned process.

In the manufacturing method of the mat material of Claim 15, after performing the baking process which bakes the said needle punching processing body, Furthermore, the impregnation process of manufacturing an impregnation mat material by impregnating the organic binder solution containing an organic binder,

A drying step of drying the impregnated mat member is performed.

According to the manufacturing method of the mat material of Claim 15, the mat material of Claim 7 can be manufactured suitably by implementing the above-mentioned process.

The silencer of Claim 16, The internal pipe in which the some small hole was formed,

Mat material wound on the side of the inner pipe,

An outer pipe in which the inner pipe wound on the side of the mat member is disposed;

A silencer provided in an exhaust path of an internal combustion engine comprising end members disposed at both ends of the outer pipe.

The mat member is a mat member according to any one of claims 1 to 7.

The muffler according to claim 16 has a mat member disposed between the inner pipe and the outer pipe that can prevent damage due to wind and heat deterioration even when the muffler is installed under high temperature conditions for use in an automobile muffler or the like.

Therefore, the silencer of Claim 16 can hold | maintain the effect which attenuates a noise for a long time. In addition, the appearance of the outer pipe is hardly damaged.

The silencer according to claim 17 includes an inner pipe in which a plurality of small holes are formed,

Mat material wound on the side of the inner pipe,

An outer pipe in which the inner pipe wound on the side of the mat member is disposed;

A silencer provided in an exhaust path of an internal combustion engine comprising end members disposed at both ends of the outer pipe.

The mat member is a mat member manufactured by the method for producing a mat member according to any one of claims 8 to 15.

The silencer according to claim 17 has a mat member disposed between the inner pipe and the outer pipe that can prevent damage due to wind and heat deterioration even when the silencer is installed under high temperature conditions for use in a silencer of an automobile.

Therefore, the silencer of Claim 17 can hold | maintain the effect which dampens a noise for a long time. In addition, the appearance of the outer pipe is hardly damaged.

In the manufacturing method of the silencer of Claim 18, Winding process which winds a mat material in the side surface of the internal pipe in which the some small hole was formed,

A press-fitting manufacturing process for press-fitting the inner pipe wound on the side of the mat member into the inside of the outer pipe to produce a press-fitting body;

A method of manufacturing a silencer, in which an end member is disposed at both ends of an outer pipe of the indented body, and then a fixing step of fixing the end member and the outer pipe of the indented body is performed.

The mat member is the mat member according to any one of claims 1 to 7, and the mat member is wound around the inner pipe so that the surface on which the inorganic fiber bundle of the mat member is formed is disposed on the outer pipe side.

According to the manufacturing method of the silencer of Claim 18, the silencer of Claim 16 can be manufactured suitably by implementing the above-mentioned process.

Moreover, in the manufacturing method of the silencer of Claim 18, the mat | matte material is wound to an inner pipe so that the surface of the said mat | matte material in which the said inorganic fiber bundle is formed and the surface whose friction coefficient is small is arrange | positioned at the outer pipe side.

Therefore, even if the inner pipe wound with the mat member is pressed into the outer pipe, the friction force between the surface of the mat member and the inner surface of the outer pipe can be reduced. Therefore, the inner pipe on which the mat member is wound can be easily pressed into the outer pipe. Therefore, in the manufacturing method of the silencer of Claim 18, the silencer of Claim 16 can be manufactured efficiently.

In addition, when the mat material according to claim 7 is used as the mat material, the inorganic fibers do not drop off even if the winding step is performed, and the dropped inorganic fibers are stuck to the operator's skin or dropped and scattered. Since the suction is rarely performed, high safety can be ensured for the worker.

In the manufacturing method of the silencer of Claim 19, Winding process which winds a mat material in the side surface of the internal pipe in which the some small hole was formed,

A press-fitting manufacturing process for press-fitting the inner pipe wound on the side of the mat member into the inside of the outer pipe to produce a press-fitting body;

A method of manufacturing a silencer, in which an end member is disposed at both ends of an outer pipe of the indenter, and then a fixing step of fixing the end member and the outer pipe of the indenter is performed.

The mat member is a mat member manufactured by the method for producing a mat member according to any one of claims 8 to 15, wherein the surface on which the inorganic fiber bundle of the mat member is formed is disposed on the outer pipe side to wind the mat member on the inner pipe. It features.

According to the manufacturing method of the silencer of Claim 19, the silencer of Claim 17 can be manufactured suitably by implementing the above-mentioned process.

Moreover, in the manufacturing method of the silencer of Claim 19, the mat | matte material is wound to an inner pipe so that the surface of the said mat | matte material in which the said inorganic fiber bundle is formed and the surface whose friction coefficient is small is arrange | positioned at the outer pipe side.

Therefore, even if the inner pipe wound with the mat member is pressed into the outer pipe, the friction force between the surface of the mat member and the inner surface of the outer pipe can be reduced. Therefore, the inner pipe on which the mat member is wound can be easily pressed into the outer pipe. Therefore, in the manufacturing method of the silencer of Claim 19, the silencer of Claim 17 can be manufactured efficiently.

In addition, when the mat material manufactured by the manufacturing method of the mat material of Claim 15 is used as a mat material, the fall of an inorganic fiber rarely arises even if a winding process is performed, and the dropped inorganic fiber sticks to an operator's skin. It is less likely to suck or loosen and scatter inorganic fibers scattered, thereby ensuring high safety for the worker.

(1st embodiment)

EMBODIMENT OF THE INVENTION Hereinafter, regarding 1st Embodiment which is one Embodiment of this invention, referring FIG. 2 (a) and FIG. 2 (b), FIG. 3, FIG. 4, and FIG. 5 (a) and FIG. 5 (b). Explain.

FIG.2 (a) is a perspective view which shows typically the state observed from one surface side regarding the example of the mat material of this embodiment, and FIG.2 (b) shows the other surface of the mat material shown in FIG.2 (a). It is a perspective view which shows typically the state observed from the side.

First, the structure of the mat material of this embodiment is demonstrated.

The mat member 10 of the present embodiment has an average fiber diameter of 3 to 10 µm and is mainly formed of an inorganic fiber containing alumina and silica. And as shown in FIG.2 (a) and FIG.2 (b), the external form is predetermined length (it shows by arrow L in FIG.2 (a)), and width (it shows by arrow W in FIG.2 (a)). ) And a thickness (indicated by an arrow T in FIG. 2A), which is a substantially rectangular flat plate.

In addition, in the following description, the surface 13a of the mat material 10 is called A surface, and the surface 13b opposite the A surface is also called B surface. And in the long side 24a of one of the cross sections 24a and 24b (henceforth a long side) parallel to the longitudinal direction of the mat material 10, the convex part 25 is formed and the other long side 24b ), A concave portion 26 is formed in which the mat member 10 is rounded to fit the convex portion 25 when the long side 24a and the long side 24b are brought into contact with each other.

As shown in Fig. 2 (a), a needle penetration mark 14 formed by needle infiltration into the mat member 10 by needle punching treatment is formed on the A surface 13a.

On the other hand, as shown in FIG.2 (b), on the B surface 13b which is the opposite side to the A surface 13a, the needle needle trace 15 formed by the needle punching-out the mat material 10 by needle punching process. Is formed. And the inorganic fiber bundle 18 by which the inorganic fiber which comprises the mat material 10 is orientated in the closed loop shape is formed in the needle bleed trace 15. As shown in FIG.

The shape of this inorganic fiber bundle 18 is demonstrated using FIG.

Fig. 3 is an optical micrograph of an inorganic fiber bundle formed on a needle bleed trace on the surface of a mat member of the present embodiment.

As shown in FIG. 3, the inorganic fiber bundle 18 has a closed loop shape having a diameter of 0.1 to 10.0 mm, and the inorganic fibers constituting the mat member 10 on the B surface 13b are in a closed loop shape. It is comprised by being oriented.

About the structure inside the mat material of this embodiment, it is the same as the structure demonstrated by description of FIG. 1 (a) mentioned above.

That is, in the inside of the mat member of the present embodiment, a plurality of needle traces extending from the needle penetration trace to the needle penetration trace are formed, and the formation density thereof is 7 to 30 pieces / cm 2. In the needle trace and the needle trace vicinity, the entanglement of an inorganic fiber has generate | occur | produced.

In addition, the mat material of this embodiment contains the organic binder which adhere | attaches inorganic fibers. In addition, the quantity of the organic binder is suppressed by the minimum amount required for bonding inorganic fibers. Therefore, when the mat material of this embodiment is used as a silencer, the amount of organic components discharged | emitted from a silencer is small, and load is hard to be applied to an environment.

Next, the structure of the silencer of this embodiment using the mat material of this embodiment is demonstrated using FIG. 4 (a) and FIG. 4 (b).

4: (a) is a perspective view which shows an example of the silencer of this embodiment typically, and FIG. 4 (b) is sectional drawing A-A of the silencer shown in FIG. 4 (a).

As shown in FIG.4 (a) and FIG.4 (b), the silencer 70 arranges the cylindrical inner pipe 73 used as a core, and the part except the both ends of the inner pipe 73 inside is arrange | positioned. Cylindrical outer pipes 71 covering the portion and end members disposed at both ends of the outer pipes 71 and having through-holes formed in the central portion, and the inner pipes 73 passing through the through-holes. It consists of 72. The size of this outer pipe 71 is shorter than the inner pipe 73, and its inner diameter is larger than the outer diameter of the inner pipe 73. As shown in FIG.

In the inside of the outer pipe 71, a plurality of small holes 74 are formed in the inner pipe 73, and the mat member 10 is disposed between the inner pipe 73 and the outer pipe 71. have.

As shown in FIG.4 (b), in the silencer 70, the arrow G shows the flow of exhaust gas in the exhaust gas which flowed in from the inlet side 73a of the internal pipe 73 (FIG.4 (b). ) Passes through the inner pipe 73 covered with the mat member 10 and the outer pipe 71, and is discharged to the outside at the outlet side 73b of the inner pipe 73.

At this time, the plurality of small pores 74 and the mat member 10 formed in the inner pipe 73 are considered to be sound absorption, diffusion, etc., especially in the high frequency region, among the noises. For that reason, these noises are considered to be attenuated.

Hereinafter, each member which comprises the silencer 70 is demonstrated using FIG. 5 (a), FIG. 5 (b), FIG. 5 (c), and FIG. 5 (d).

5 (a), 5 (b), 5 (c) and 5 (d) each show an example of a mat member, an inner pipe, an outer pipe and an end member constituting the silencer of the present embodiment in order. It is a perspective view which shows typically.

In addition, since the structure of the mat material 10 of this embodiment used for the silencer 70 shown to FIG. 5 (a) was already demonstrated, description is abbreviate | omitted.

In addition, the inner pipe 73 shown to FIG. 5 (b) is mainly comprised from metals, such as stainless steel. Since the structure of the inner pipe 73 is already described, description is abbreviate | omitted.

First, the outer pipe 71 will be described. As shown in FIG.5 (c), the outer pipe 71 is a cylindrical structure mainly consisting of metals, such as stainless steel. The inner diameter is slightly smaller than the outer diameter of the mat member 10 in the state wound around the inner side of the inner pipe 73. Moreover, the length is shorter than the inner pipe 73.

Subsequently, the end member 72 will be described. As shown in FIG.5 (d), the end member 72 is a disk-shaped structure mainly consisting of metals, such as stainless steel. In addition, the diameter is substantially the same as the outer diameter of the outer pipe 71. In the vicinity of the center, a through hole 75 having a diameter substantially equal to the outer diameter of the inner pipe 73 is formed.

Hereinafter, the method of manufacturing the mat material and the silencer of this embodiment is demonstrated. First, the manufacturing method of a mat material is demonstrated.

(1) spinning process

In the basic aqueous aluminum chloride solution prepared so that the Al content and the atomic ratio of Al and Cl are a predetermined value, the composition ratio in the inorganic fiber after firing is Al ₂ O ₃ : SiO ₂ = 60: 40 to 80:20 (weight ratio) Silica sol is added to this. Moreover, for the purpose of improving moldability, an appropriate amount of organic polymer is added to prepare a mixed liquid.

The obtained liquid mixture is concentrated to make a spinning mixture, and the spinning mixture is spun by a blowing method to prepare an inorganic fiber precursor having an average fiber diameter of 3 to 10 µm.

In addition, in this specification, a blowing method means the method of spinning an inorganic fiber precursor by supplying the spinning mixture extruded from a spinning mixture supply nozzle to the high speed gas stream (air flow) sprayed from an air nozzle.

(2) compression process

Next, the inorganic fiber precursor is compressed to produce a continuous sheet-like article of a predetermined size.

(3) needle punching process

Above the one surface of the said sheet-like thing, the needle board in which the needle was mounted by the density of 7-30 pieces / cm <2> is arrange | positioned. And a needle punching process is performed by moving a needle board up and down once along the thickness direction of a sheet-like thing, and a needle punching process body is produced. In this case, the needle is penetrated until the barb formed in the tip portion of the needle is completely exposed to the opposite surface of the sheet-like object.

Needle penetration marks are formed at the point where the needles on the surface of the needle punching treatment body obtained by the needle punching treatment are intruded, and needle extraction traces are formed at the points where the needles on the surface of the needle punching treatment body are infiltrated. In the needle bleed trace, a bundle-shaped inorganic fiber precursor in which the inorganic fiber precursor is oriented in a closed loop shape is formed.

(4) firing process

Subsequently, the needle punching treatment body is continuously fired at a maximum temperature of about 1000 to about 1600 ° C to produce a fired sheet-like article.

(5) cutting process

Next, the fired sheet-like article is cut to produce a cut sheet-like article of a predetermined size.

(6) impregnation process

The organic binder solution is flow-coated to the cut sheet-like article to impregnate the cut sheet-like article with the organic binder to produce an impregnated sheet-like article.

(7) drying process

After the excess organic binder solution is removed by suction from the impregnated sheet, the dried sheet-like article containing the organic binder is produced by pressure drying.

(8) forming cutting process

The said dry sheet-like thing is shape | molded and cut, The mat material which consists mainly of inorganic fiber is formed in the concave part of predetermined shape, and formed in the long side of one side, and the convex part of the shape fitted with the recessed part on the other long side.

By the above process, the mat material of this embodiment is manufactured.

Moreover, the mat material of this embodiment manufactured in this way becomes a mat material which has a some needle trace which advances from the needle penetration trace formed in the A surface to the needle penetration trace formed in the B surface. In addition, an inorganic fiber bundle in which a plurality of inorganic fibers are oriented in a closed loop shape in the needle ejection trace is formed, and a mat member having an inorganic fiber bundle is formed on the B surface. Furthermore, it becomes a mat material containing an organic binder.

Hereinafter, the manufacturing method of the silencer using the mat material of this embodiment is demonstrated using FIG.

FIG. 6: is a perspective view which shows typically the state which manufactures a silencer using the inner pipe, mat material, outer pipe, and end member shown to FIGS. 5 (a)-(d).

(1) winding process

A cylindrical inner pipe 73 having a plurality of small holes 74 is prepared, and the mat surface 10 of the present embodiment has a B surface on the outer pipe 71 side (outside), and an A surface on the inner pipe 73. ) To the side (inner side) and wound on the side surface of the inner pipe (73).

(2) indentation manufacturing process

The inner pipe 73 on which the mat member 10 is wound is pressed into the cylindrical outer pipe 71 to produce a press-fit body.

(3) fixed process

First, two end members 72 are prepared. And the end member 72 is arrange | positioned at the both ends of the outer pipe 71 so that the inner pipe 73 of a press-fit body may penetrate the through-hole 75 of each end member 72. Next, the outer pipe 71 and the end member 72 are fixed by fixing means such as welding, and the vicinity of the through-hole 75 of the inner pipe 73 and each end member 72 is fixed. It is fixed by fixing means, such as welding.

By the above process, the press-fitting body manufactures the silencer arrange | positioned inside an outer pipe.

Hereinafter, the effect of the mat member of the first embodiment, the manufacturing method of the mat member, the silencer, and the manufacturing method of the silencer will be listed.

(1) The mat member of the present embodiment has a plurality of needle traces formed by a needle punching process that advances from a needle penetration trace formed on the surface to a needle penetration trace formed on the surface opposite to the surface on which the needle penetration trace is formed.

When the mat material of this embodiment which has such a structure is used for a silencer, since the interlayer strength of the whole mat material is high, damage to a mat material by wind-weather can be prevented. Therefore, the effect of damping noise can be maintained for a long time. Moreover, since the heat insulating property of a mat material is not impaired easily, it can be set as a mat material which does not damage the external pipe well.

(2) In the needle ejection trace in the mat member of the present embodiment, an inorganic fiber bundle in which a plurality of inorganic fibers are oriented in a closed loop shape is formed, and an inorganic fiber bundle is formed on at least one surface.

When manufacturing a silencer using the mat material of this embodiment which has such a structure, the inner pipe by which the mat material was wound is made easy to an outer pipe by making the surface in which the inorganic fiber bundle was formed into the outer pipe side, and winding the mat material to the inner pipe. Can be press-fitted. Therefore, it can be set as the mat member excellent in handleability.

(3) In addition, when manufacturing a silencer using the mat material of this embodiment which has such a structure, since the inorganic fiber which comprises an inorganic fiber bundle has few fluffs, inorganic fiber sticks to an operator's skin. little. Therefore, it can be set as the mat material with high stability for an operator.

(4) In the mat member of the present embodiment, the average fiber diameter of the inorganic fibers constituting the mat member is 3 to 10 µm. In addition, the formation density of the needle trace is 7-30 pieces / cm <2>. Therefore, it can be set as the mat material with higher interlayer strength of the whole.

Therefore, when the mat material of this embodiment is used for a silencer, the effect which attenuates a noise can be maintained over a longer period.

(5) In addition, as described above, the mat material of the present embodiment has a formation density of needle traces of 7 to 30 pieces / cm 2. Therefore, the frictional force between the surface of the mat member and the inner surface of the outer pipe can be further reduced.

Therefore, when manufacturing a silencer using the mat material of this embodiment, the inner pipe by which the mat material was wound can be press-fitted to an outer pipe more easily, and it can be set as a mat material excellent in handleability.

(6) The mat member of the present embodiment is made of an inorganic fiber containing alumina and silica, and is excellent in heat resistance. Therefore, even when the silencer using the mat material of this embodiment is installed in an exhaust path and a high temperature exhaust gas generate | occur | produces, an inorganic fiber does not melt | dissolve easily.

Therefore, even when the temperature of the exhaust gas becomes high, the effect of damping noise can be maintained for a longer period of time.

(7) In the mat member of the present embodiment, the inorganic fibers constituting the mat member are bonded to each other by an organic binder, so that the inorganic fibers constituting the mat member are unlikely to fall off.

Therefore, when manufacturing a muffler using the mat material of this embodiment, even if processing, such as winding a mat material with respect to an internal pipe, the fall of an inorganic fiber does not occur easily and high stability for an operator is performed. I can do it with mat material.

(8) In the manufacturing method of the mat material of this embodiment, the mat material of this embodiment can be manufactured preferably by going through the process mentioned above.

(9) In the silencer of the present embodiment, the mat member of the present embodiment capable of exhibiting the above-described effects of (1) to (7) is disposed between the inner pipe and the outer pipe. In particular, by the effect of the (1), (4), and (6) which the mat member of this embodiment has, the silencer of this embodiment can hold | maintain the effect which attenuates a noise for a long time. In addition, the appearance of the outer pipe is hardly damaged.

(10) In the manufacturing method of the silencer of this embodiment, the silencer of this embodiment is manufactured using the mat material of this embodiment which can exhibit the effect of (2) and (5) mentioned above.

That is, in the manufacturing method of the silencer of this embodiment, the mat material is wound around an inner pipe so that the surface of the mat material of this embodiment may have the inorganic fiber bundle and the surface with a small friction coefficient arrange | positioned on the outer pipe side. Then, the inner pipe wound with the mat member is pressed into the outer pipe to manufacture the silencer of the present embodiment. Therefore, the frictional force between the surface of the mat member and the inner surface of the outer pipe can be reduced. Therefore, the inner pipe wound with the mat member can be easily pressed into the outer pipe.

Therefore, in the manufacturing method of the silencer of this embodiment, the silencer of this embodiment can be manufactured efficiently.

(11) In the manufacturing method of the silencer of this embodiment, the silencer of this embodiment is manufactured using the mat material of this embodiment which can exhibit the effect of (3) mentioned above.

That is, in the manufacturing method of the silencer of this embodiment, each inorganic fiber which comprises an inorganic fiber bundle is orientated in the closed loop shape, and a silencer is manufactured using the mat material of this embodiment with little fluff of inorganic fiber. .

Moreover, in the manufacturing method of the silencer of this embodiment, the silencer of this embodiment is manufactured using the mat material of this embodiment which can exhibit the effect of above-mentioned (7).

That is, in the manufacturing method of the silencer of this embodiment, since an inorganic fiber adhere | attaches each other with an organic binder, a silencer is manufactured using the mat material of this embodiment in which fallout of an inorganic fiber does not occur easily.

Therefore, in the manufacturing method of the silencer of this embodiment, high safety can be ensured for an operator.

Hereinafter, although the Example which showed 1st Embodiment of this invention more concretely is shown, this embodiment is not limited only to these Examples.

(Example 1)

1. Manufacture of mat material

The mat member was manufactured by the following procedures.

(1-1) spinning process

The composition ratio in the inorganic fiber after baking was Al ₂ O ₃ : SiO ₂ = 72: 28 (based on the aqueous aluminum chloride solution prepared so that the Al content was 70 g / L and Al: Cl = 1: 1.8 (atomic ratio)). Silica sol was mix | blended so that it might become weight ratio), and also the organic polymer (polyvinyl alcohol) was added appropriately and the mixed liquid was prepared.

The obtained liquid mixture was concentrated to make a spinning mixture, and the spinning mixture was spun by a blowing method to prepare an inorganic fiber precursor having an average fiber diameter of 5.1 mu m.

(1-2) Compression Process

The inorganic fiber precursor obtained at the said process (1-1) was compressed, and the continuous sheet form was produced.

(1-3) Needle Punching Process

About the sheet-like thing obtained by the said process (1-2), the needle punching process was performed continuously using the conditions shown below, and the needle punching process body was produced.

First, a needle board on which needles were mounted at a density of 21 pieces / cm 2 was prepared. Next, the needle board was placed above one surface of the sheet-like article, the needle punching treatment was performed by moving the needle board up and down once along the thickness direction of the sheet-like article to produce a needle punching treatment body. . At this time, the needle was penetrated until the barb formed at the tip portion of the needle completely penetrated the surface on the opposite side of the sheet-like object.

(1-4) firing process

The needle punching process body obtained at the said process (1-3) was baked continuously at the maximum temperature of 1250 degreeC, and the baking sheet form which consists of inorganic fibers containing alumina and a silica was manufactured. It was confirmed that the needle fiber trace formed an inorganic fiber bundle in which the inorganic fibers were oriented in a closed loop shape. The formation density of the inorganic fiber bundle was 21 pieces / cm 2.

Moreover, the average fiber diameter of the inorganic fiber was 5.1 micrometers, and the minimum value of the inorganic fiber diameter was 3.2 micrometers.

(1-5) cutting process

The fired sheet-like article obtained in the said process (1-4) was cut | disconnected, and the cut sheet-like article was produced.

(1-6) Impregnation Process

The impregnated sheet-like object was produced by flow-coating the organic binder solution (acrylic-type latex) containing acrylic resin as an organic binder, and impregnating an organic binder in the cut sheet-like object obtained by the said process (1-5).

(1-7) drying process

After removing the excess organic binder solution by suction from the impregnation sheet form obtained in the said process (1-6), it dried under pressure and produced the dry sheet form containing an organic binder. Moreover, the quantity of the organic binder contained in the produced dry sheet form was 1 weight%.

(1-8) molding cutting process

The dry sheet-like article obtained in the step (1-7) was molded and cut to have a width of 239 mm × length 500 mm × thickness 7.4 mm, and the formation density of needle traces was 21 pieces / cm 2, weight 1240 g / m 2 per unit area, and density. It is 0.16 g / cm <3>, and width (size of the part parallel to the width direction of a dry sheet-like thing) 50 mm x length (size of the part parallel to the longitudinal direction of a dry sheet-like thing) 150 mm in a part of one long side A mat having a convex portion (25 in FIG. 2 (a)) protruding over and formed with a concave portion (26 in FIG. 2 (a)) shaped to fit the convex portion on a part of the other long side. Ash was prepared.

The needle penetration mark was formed at the point where the needle of one surface of the mat material manufactured in this way penetrated. In addition, the needle bleeding trace was formed at the point where the needle on the other surface of the mat member was pierced. And needle traces progressed from the needle penetration trace to the needle penetration trace (21 needle density / cm 2 of needle trace).

Moreover, it was confirmed that the inorganic fiber bundle which the inorganic fiber orientates in the closed loop shape is formed in almost all the needle outbreak traces.

On the other hand, regarding the formation density of the needle traces, the mat member was cut into roughly two portions with respect to the thickness direction thereof, and was calculated from the number of needle traces that could be confirmed by the naked eye per unit area of the cross section. In addition, the needle penetration trace, the needle penetration trace, and the presence or absence of an inorganic fiber bundle were implemented by visually observing the surface of each mat material.

2. Manufacture of silencers

(2-1) winding process

First, an inner pipe having a plurality of small pores formed on the side was prepared in a cylindrical shape having an outer diameter of 70 mm (inner diameter 67 mm) and a length of 600 mm.

Next, the mat member obtained in the above step (1-8) has an inner pipe such that the surface (surface B surface) on which the needle penetration trace (inorganic fiber bundle) is formed is the outer side and the surface (A surface) on which the needle penetration trace is formed is the inner side. Wound on its side.

(2-2) Indentation Production Process

The press-fitting body was produced by pressing the inner pipe by which the mat | matte material obtained by the said process (2-1) was wound to the inside of the cylindrical outer pipe of an outer diameter of 82 mm (inner diameter 79 mm x length 500 mm length).

(2-3) fixed process

First, two end members were prepared. And the end member was arrange | positioned at the both ends of an outer pipe through the inner pipe of the press fit body obtained by the said process (2-2) in the through-hole of each end member. Next, the outer pipe and the end member were fixed by welding. Moreover, the vicinity of the through-hole of the inner pipe and each end member was fixed by welding.

By the above process, the silencer in which the inner pipe in which the mat | matte material was wound by the side was arrange | positioned inside the outer pipe was manufactured.

(Interlayer Strength Measurement Test)

The interlayer strength measurement test was performed using the interlayer strength measurement apparatus 80 shown in Fig. 7A. FIG. 7: (a) is explanatory drawing of the interlayer strength measurement apparatus, and FIG. 7 (b) is a perspective view which shows typically the shape of the sample 2 for interlayer strength measurement.

The interlayer strength measuring device 80 uses an Instron universal testing machine (Instron Co., Ltd., 5567), and the lower chuck 81a fixed to the tester main body (not shown) and the upper chuck moving in the vertical direction ( 81b). The lower chuck 81a and the upper chuck 81b have gripping portions 82a and 82b for holding the peeling portions 3a and 3b of the sample 2, respectively.

The test method using this interlayer strength measuring device 80 is as follows.

First, as shown to FIG. 7 (b), the mat material manufactured in Example 1 was cut out in width 50mm x length 200mm, and it was set as the sample 2. In addition, as the sample 2, in order to remove the influence of an organic binder, the mat material which does not contain the organic binder manufactured without performing the said process (1-6) and the said process (1-7) was used.

Next, the sheath 3 was put into the cutter so that the sample 2 may be divided roughly into 2 parts with respect to the thickness direction in one cross section in the width direction of the sample 2. Next, peeling parts 3a and 3b were formed in one end surface in the width direction of sample 2 by peeling sample 2 along the sheath 3 in the longitudinal direction.

And, among the peeling parts 3a and 3b, one peeling part 3a is gripped by the gripper 82a of the lower chuck 81a, and the other peeling part 3b is gripped by the upper chuck 81b. It was gripped by (82b).

In this state, the upper chuck 81b is moved vertically upward (in the direction indicated by the arrow B in FIG. 7) so that the tensile speed is 10 mm / min, and the maximum load (N when the sample is completely peeled in two) ) Was measured. This measurement was performed 3 times and the average value was made into the interlayer strength of the whole mat material.

As a result, the interlayer strength of the whole mat material manufactured in Example 1 was 3.6N.

(Friction coefficient measurement test)

The friction coefficient measurement test was performed using the friction coefficient measuring apparatus as shown in FIG.

8 is an explanatory diagram of a friction coefficient measuring device.

The friction coefficient measuring device 90 is provided on the upper surfaces of the lower plate member 94a, the upper plate member 94b, and the upper plate member 94b made of stainless steel sandwiching the sample 4 for measuring the friction coefficient in the vertical direction. And a wire 96 connected to a load cell moving in a vertical direction of an instron type universal testing machine (not shown). The lower plate member 94a is fixed to a base not shown so as not to move, and a wire 96 is coupled to the upper plate member 94b. The wire 96 connects the upper plate member 94b and the load cell through the pulley 97. Therefore, when the load cell moves upward in the vertical direction, the upper plate member 94b moves in the horizontal direction (direction indicated by arrow C in FIG. 8).

The test method using this friction coefficient measuring device 90 is as follows.

First, the mat material manufactured in Example 1 was cut out to width 30mm x length 50mm, and it was set as the sample 4 for friction coefficient measurement.

Next, one surface of the sample 4 is fixed on the fixed lower plate member 94a so that the longitudinal direction of the sample 4 is parallel to the moving direction of the upper plate member 94b, and on the other surface of the sample 4 By providing the upper plate member 94b, the sample 4 was sandwiched between the lower plate member 94a and the upper plate member 94b in the vertical direction. And the 5 kg weight 95 was provided in the upper surface of the upper board member 94b.

In this state, the upper plate member 94b was moved at a movement speed of 10 mm / min in the horizontal direction by moving the load cell vertically upward so that the tensile speed was 10 mm / min. Then, after moving the upper plate member 94b, the stress after 120 seconds was measured, and the friction coefficient between the other surface of Sample 4 and the upper plate member 94b was calculated. The obtained friction coefficient was made into the friction coefficient of the surface of a mat material.

In addition, this measurement was performed with respect to both surfaces of a mat material.

As a result, the coefficient of friction of the surface of the mat member produced in Example 1 was 0.25 on the A surface and 0.22 on the B surface, respectively.

(Examples 2 and 3 and Reference Examples 1 and 2)

In the step (1-1) of Example 1, the conditions for spinning the spinning mixture by the blowing method are changed so that the average fiber diameter of the inorganic fibers constituting the mat member is the value shown in Table 1, and is shown in Table 1 A mat member and a silencer were prepared in the same manner as in Example 1 except that an inorganic fiber precursor having an average fiber diameter approximately equal to the value was produced.

(Examples 4 and 5 and Reference Examples 3 and 4)

In the step (1-3) of Example 1, needle punching is carried out using a needle board on which needles are mounted at a density approximately equal to the values shown in Table 1 so that the formation density of the needle traces in the mat member becomes the value shown in Table 1. A mat member and a silencer were produced in the same manner as in Example 1 except that the treatment was performed.

(Comparative Example 1)

A mat member and a silencer were produced in the same manner as in Example 1 except that the step (1-3) of Example 1 was not performed.

(Comparative Example 2)

In the step (1-3) of Example 1, the mat member and the mat member and the mating depth of the needle in the needle punching process were changed in the same manner as in Example 1 except that the needle was not ejected to the opposite surface of the sheet-like object. A silencer was prepared.

In the mat material manufactured by these comparative examples 1 and 2, neither the inorganic fiber bundle was formed in the surface of the mat material.

About the mat materials manufactured in Examples 2-5, Reference Examples 1-4, and Comparative Examples 1 and 2, the interlayer strength measurement test and the friction coefficient measurement test were carried out in the same manner as in Example 1, and the interlayer of the entire mat material was The strength and friction coefficient of the surface of the mat member were evaluated. The result in each Example, each reference example, and each comparative example is shown in Table 1 with the result of Example 1. FIG.

(Note 1) Although needle punching treatment was performed, all needles were not ejected to the opposite surface of the sheet-like object by changing the penetration depth of the needle.

(Note 2) In the needle punching process, the formation density (number / cm 2) of the needles formed on the needle board is shown.

As a result, in the mat material manufactured in Examples 1-5, the interlayer strength of the whole mat material could all be made higher than the mat material manufactured by each comparative example. Therefore, in the silencer using the mat material of Example 1 which has such a structure, it is thought that the case where an inorganic fiber peels by the stress accompanying the flow of exhaust gas is less than the mat material manufactured by each comparative example. Therefore, it is thought that the damage of the mat material by wind-weather can be prevented more efficiently.

Moreover, in the mat material manufactured in Examples 1-5, the friction coefficient of the surface in which the inorganic fiber bundle was formed was made lower than the mat material manufactured by each comparative example. Therefore, the mat material which was more excellent in handleability was made.

On the other hand, in the mat materials manufactured in Comparative Examples 1 and 2, the interlayer strength was low because no entanglement of the inorganic fibers was generated or no entanglement of the inorganic fibers was generated throughout the thickness direction of the mat portion. In addition, since the inorganic fiber bundle was not formed, the friction coefficient was high on both surfaces of the mat member.

In addition, in the mat member manufactured in Reference Example 1, the interlayer strength of the entire mat member was significantly higher than that of the mat member manufactured in each of the comparative examples, similarly to the mat member manufactured in the respective examples, but the average fiber diameter of the inorganic fiber was It was because the strength of the inorganic fiber itself fell below 3 micrometers, or the interlayer strength of the whole mat material was slightly lower than the mat material manufactured in Example 1.

In the mat member manufactured in Reference Example 2, the interlayer strength of the entire mat member was significantly higher than that of the mat member manufactured in each of the comparative examples, similarly to the mat member manufactured in the respective examples, but the average fiber diameter of the inorganic fiber was 10. The interlaminar strength of the entire mat material was slightly lower than that of the mat material produced in Examples 1 to 3 because the number of inorganic fibers constituting the mat material per unit volume exceeded the micrometer, and the number of inorganic fibers was small.

In the mat member manufactured in Reference Example 3, the interlaminar strength of the entire mat member was significantly higher than that of the mat member manufactured in each of the comparative examples, similarly to the mat member manufactured in the respective examples, but the formation density of the needle traces was seven. It was because the number of needle traces formed per unit area was less than / cm 2, and the interlayer strength of the entire mat material was slightly lower than that of the mat material produced in Example 1. Moreover, the coefficient of friction of the surface in which the inorganic fiber bundle was formed was slightly higher than the mat material manufactured in each Example.

In the mat member manufactured in Reference Example 4, the interlaminar strength of the entire mat member was significantly higher than that of the mat member manufactured in each comparative example, similarly to the mat member manufactured in each example, but the formation density of the needle traces was 30 pieces. Whether the inorganic fibers (inorganic fiber precursors) were partially cut into more than / cm 2, the interlayer strength of the entire mat material was slightly lower than that of the mat material produced in Example 1.

Thus, although the mat material manufactured by the reference examples 1-4 can fully exhibit the effect of this embodiment, the average fiber diameter of the inorganic fiber which comprises a mat material is 3-10 micrometers, or needle needle formation It turned out that it is preferable that the density is 7-30 piece / cm <2>.

Furthermore, it turned out that it is more preferable if the average fiber diameter of the inorganic fiber which comprises a mat material is 3-10 micrometers, and the formation density of a needle trace is 7-30 pieces / cm <2>.

(2nd embodiment)

Next, 2nd Embodiment which is one Embodiment of this invention is described, referring FIG. 9 (a), FIG. 9 (b), and FIG. 9 (c).

FIG. 9 (a) is a perspective view schematically showing a state observed from one surface side with respect to an example of the mat member of the present embodiment, and FIG. 9 (b) shows the other surface of the mat member shown in FIG. 9 (a). It is a perspective view which shows typically the state observed from the side. FIG. 9 (c) is a cross-sectional view taken along a line D-D schematically illustrating a cross section obtained by cutting the mat member shown in FIG. 9 (a) in a direction perpendicular to the longitudinal direction.

The mat member of the present embodiment is formed from an inorganic fiber containing alumina and silica, and as shown in Figs. 9A, 9B, and 9C, the outer shape is the mat of the first embodiment. Like ash, it is a flat plate shape having a predetermined thickness in a substantially rectangular shape when viewed from the top.

Since the other structure regarding the external shape of the mat member of this embodiment is the same as that of 1st embodiment, description is abbreviate | omitted.

As shown to FIG.9 (a), FIG.9 (b) and FIG.9 (c), the needle mat material is in the surface 113a (henceforth a 1st surface) of the mat material 100 of this embodiment. A first needle penetration mark 114a formed by penetration into the first surface 113a of the 100 is formed.

In addition, the needle penetrates into the second surface 113b of the mat member 100 on the surface 113b (hereinafter also referred to as a second surface) opposite to the first surface 113a among the surfaces of the mat member 100. The formed 2nd needle penetration mark 114b is formed.

* And the 1st surface 113a of the mat material 100 is located in the 1st surface 113a of the mat material 100 at the position corresponding to the needle penetration mark 114b formed in the 2nd surface 113b. A plurality of second needle bleeding traces 115b formed by bleeding from each other are formed. And the 2nd needle fiber trace 115b is provided with the 2nd inorganic fiber bundle 118b by which the inorganic fiber which comprises the mat material 100 is oriented in a closed loop shape.

In addition, the needle is formed on the second surface 113b of the mat member 100 at the second surface 113b of the mat member 100 at a position corresponding to the needle penetration mark 114a formed on the first surface 113a. A plurality of first needle bleeding marks 115a formed by piercing are formed. And the 1st inorganic fiber bundle 118a by which the inorganic fiber which comprises the mat material 100 is orientated in the closed loop shape is formed in the 1st needle penetration trace 115a.

As shown to Fig.9 (c), about the internal structure of the mat material 100 of this embodiment, similarly to the structure of 1st Embodiment mentioned above, it is the 1st needle from the 1st needle penetration mark 114a. A plurality of first needle traces 116a extending to the bleed traces 115a are formed, and entanglement of the inorganic fibers is generated in the vicinity of the first needle traces 116a and the first needle traces 117a. In addition, adjacent to the first needle trace 116a, a plurality of second needle traces 116b, which are advanced from the second needle penetration trace 114b to the second needle penetration trace 115b, are formed, and the second needle Also in the trace 116b and the vicinity of the 2nd needle trace 117b, the entanglement of an inorganic fiber generate | occur | produces.

As described above, in the mat member 100 of the present embodiment, the direction in which the needle traces progress in the first needle trace 116a and the second needle trace 116b is mutually opposed to each other. Therefore, the directions of the entanglement of the inorganic fibers in the first needle trace 116a and the vicinity of the first needle trace 117a, the second needle trace 116b and the vicinity of the second needle trace 117b are different from each other, and the mat Inorganic fibers are more intricately intertwined throughout the ash 100.

About the other structure of the mat material 100 of this embodiment, the formation density of the total needle trace including the 1st needle trace 116a and the 2nd needle trace 116b is 7-30 piece / cm <2>. Other than that, it has the same structure as the mat member of 1st Embodiment. Moreover, the formation density of the 1st needle trace 116a and the formation density of the 2nd needle trace 116b are the same.

Moreover, the formation density of the 2nd inorganic fiber bundle 118b formed in the 1st surface 113a, and the formation density of the 1st inorganic fiber bundle 118a formed in the 2nd surface 113b differ from each other.

The silencer of the present embodiment has the same configuration as the silencer of the first embodiment except that the mat member of the present embodiment is used.

Hereinafter, the manufacturing method of the mat material and the silencer of this embodiment is demonstrated.

First, the manufacturing method of a mat material is demonstrated.

First, a sheet-like article is produced by going through a spinning step and a compression step as in the first embodiment.

Next, two needle boards on which needles are mounted at different densities are prepared, and one needle board is spaced apart from the second surface of the sheet-like article. And the needle punching process of a 1st time is performed by moving the needle board up and down along the thickness direction of a sheet-like thing. Next, the other needle board is spaced apart from the first surface of the sheet-like article, the needle board is moved up and down along the thickness direction of the sheet-like article, and the second needle punching treatment is performed to form the needle punching treatment body. To make. In this case, the needles are penetrated to both sides of the sheet-like article until the barb formed at the tip portion of the needle is completely exposed to the opposite surface of the sheet-like article.

Further, depending on the needle formation density, two needle boards on which needles are mounted at the same density as each other may be used as the needle boards. Also by using such a needle board, the needle punching treatment body which differs from the formation density of the 2nd inorganic fiber bundle formed in the 1st surface and the formation density of the 1st inorganic fiber bundle formed in the 2nd surface by implementing the above-mentioned process is carried out. I can make it.

This is, once, by performing a second needle punching treatment on the first surface on which the bundle-shaped inorganic fiber precursor is formed, a part of the bundle-shaped inorganic fiber precursor formed on the first surface is again drawn into the needle punching treatment body by the needle. It is considered that part of the bundle-shaped inorganic fiber precursor formed on the first surface is lost. For this reason, in order to produce the needle punching processing body from which the formation density of the 2nd inorganic fiber bundle formed in the 1st surface and the formation density of the 1st inorganic fiber bundle formed in the 2nd surface differ from each other, the needle board with a high needle formation density is used. It is preferable to use. If the needle formation density is too low, in the second needle punching treatment, the needles are introduced at positions away from the bundle-shaped inorganic fiber precursors formed on the first surface. Therefore, it is because it is difficult for the bundle-shaped inorganic fiber precursor to be drawn into the needle punching processing body by the needle.

As described above, in order to fabricate a needle punching processing body having a different density of formation of the second inorganic fiber bundle formed on the first surface and the formation density of the first inorganic fiber bundle formed on the second surface, two needles having needles mounted at different densities from each other are formed. A board may be used, or two needle boards with needles mounted at the same density may be used depending on the needle formation density.

The mat member of the present embodiment is produced by carrying out the firing step, the cutting step, the impregnation step, the drying step, and the molding cutting step in the same manner as in the first embodiment with respect to the obtained needle punching processing body.

In the manufacturing method of the silencer of this embodiment, among the 1st and 2nd surfaces of the mat material of this embodiment, the surface with many inorganic fiber bundles is arrange | positioned on the outer pipe side (outside), and the inorganic fiber bundle which is the opposite side to this is A silencer of the present embodiment is produced in the same manner as in the manufacturing method of the silencer of the first embodiment except that a small surface is disposed on the inner pipe side (inner side) to produce a silencer.

Also in 2nd Embodiment mentioned above, the effect (1)-(11) demonstrated by 1st Embodiment can be exhibited.

Moreover, the following effects can be exhibited.

(12) In the mat member of the present embodiment, first needle traces and second needle traces, in which the direction of progress of the needle traces face each other, are formed.

Therefore, it can be set as the mat material with higher interlayer strength of the whole.

Therefore, when the mat material of this embodiment is used for a silencer, the effect which attenuates a noise can be maintained over a longer period.

(13) In the silencer of the present embodiment, the mat member of the present embodiment capable of exhibiting the effect of (12) described above is disposed between the inner pipe and the outer pipe.

Therefore, the muffler of this embodiment can hold | maintain the effect which attenuates a noise for a long time. In addition, the appearance of the outer pipe is less likely to be damaged.

(14) In the mat member of the present embodiment, the forming density of the second inorganic fiber bundle formed on the first surface is different from the forming density of the first inorganic fiber bundle formed on the second surface. Therefore, when manufacturing a silencer using the mat material of this embodiment, the surface with many inorganic fiber bundles is arrange | positioned on the outer pipe side (outer side) among the surfaces of the mat material of this embodiment, and the opposite side to it. The surface with few phosphorus inorganic fiber bundles can be arrange | positioned at the inner pipe side (inner side). Therefore, the interlayer strength of the entire mat member can be made higher while minimizing the separation of the inorganic fibers on the mat member surface by the stress accompanying the flow of the exhaust gas on the surface of the mat member disposed on the inner pipe side. In addition, the inner pipe wound with the mat member can be easily pressed into the outer pipe.

Therefore, when the mat material of this embodiment is used for a silencer, the effect which attenuates a noise can be maintained for a longer period.

(15) In the muffler of the present embodiment, since the mat member of the present embodiment capable of exhibiting the above-described effect of (14) is disposed between the inner pipe and the outer pipe, the effect of damping the noise for a longer period of time. I can keep it on. In addition, the appearance of the outer pipe is less likely to be damaged.

Hereinafter, the Example which disclosed 2nd Embodiment of this invention more concretely is shown. In addition, 2nd Embodiment is not limited only to these Examples.

(Example 6)

In the step (1-3) of Example 1, the mat member and the silencer were produced in the same manner as in Example 1 except that the needle punching treatment was performed on the sheet-like article under the following conditions. .

First, two needle boards on which needles were mounted at a density of 10 / cm 2 were prepared. Next, one needle board was separated and arrange | positioned at the 2nd surface of a sheet-like thing. And the needle punching process of the 1st time was performed by moving the needle board up and down once along the thickness direction of a sheet-like thing. Next, the other needle board is spaced apart from the first surface of the sheet-like article, the needle board is moved up and down along the thickness direction of the sheet-like article, and the second needle punching treatment is performed to form the needle punching treatment body. Produced. In this case, the needle was penetrated until the barb formed in the tip portion of the needle was completely exposed to the opposite surface of the sheet-like object.

The 1st needle penetration mark was formed in the point which the needle of the 1st surface of the mat material manufactured using the needle punching process body mentioned above penetrated. Moreover, the 1st needle bleeding trace was formed in the point where the needle of the 2nd surface of the mat material was pierced. And it was confirmed that the inorganic fiber bundle in which the inorganic fiber is oriented in the closed loop shape is formed in the first needle trace.

Moreover, the 2nd needle penetration trace was formed in the point which the needle of the 2nd surface of the obtained mat material penetrated. Moreover, the 2nd needle bleeding trace was formed in the point where the needle of the 1st surface of the mat material was pierced. And it was confirmed that the inorganic fiber bundle in which the inorganic fiber is oriented in the closed loop shape is formed in the second needle bleed trace.

The formation density of the second inorganic fiber bundle formed on the first surface was 2 pieces / cm 2, and the formation density of the first inorganic fiber bundle formed on the second surface was 7 pieces / cm 2. In addition, the formation density of the total needle trace including the first needle trace and the second needle trace was 20 pieces / cm 2.

In addition, the formation density of the 1st inorganic fiber bundle and the formation density of the 2nd inorganic fiber bundle were implemented by visually observing the number of the inorganic fiber bundles which exist per unit area of each surface of a mat material.

In the manufactured mat material, the formation density of the inorganic fiber bundle was slightly smaller than the formation density of the needle trace. For this reason, as described above, the needle punching treatment is once again performed from the first surface side where the bundle-shaped inorganic fiber precursor is formed, so that a part of the bundle-shaped inorganic fiber precursor formed on the first surface is needle punched treatment body again. You can think of being dragged into me.

(Example 7, 8)

Inorganic fiber precursors having an average fiber diameter approximately equal to the value shown in Table 2 by changing the conditions for spinning the spinning mixture by the blowing method so that the average fiber diameter of the inorganic fibers constituting the mat member is the value shown in Table 2. A mat material and a silencer were manufactured in the same manner as in Example 6 except that the product was manufactured. The density of formation of the second inorganic fiber bundle formed on the first surface, the formation density of the first inorganic fiber bundle formed on the second surface, and the formation density of the needle traces in total including the first needle trace and the second needle trace Was the same as

(Examples 9 and 10)

Example 6 except that needle punching treatment was performed using two needle boards (Example 9) mounted at a density of 7 needles / cm 2 or two needle boards (Example 10) mounted at a density of 14 needles / cm 2. In the same manner as to prepare a mat material and a silencer.

In Example 9, the formation density of the second inorganic fiber bundle formed on the first surface was 1 piece / cm 2, and the formation density of the first inorganic fiber bundle formed on the second surface was 5 pieces / cm 2. In addition, the formation density of the total needle trace including the first needle trace and the second needle trace was 14 pieces / cm 2.

In Example 10, the formation density of the second inorganic fiber bundle formed on the first surface was 2.5 pieces / cm 2, and the formation density of the first inorganic fiber bundle formed on the second surface was 10 pieces / cm 2. In addition, the formation density of the total needle trace including the first needle trace and the second needle trace was 28 pieces / cm 2.

About the mat material manufactured in Examples 6-10, the interlayer strength measurement test and the friction coefficient measurement test were implemented by the method similar to Example 1, and the interlayer strength of the whole mat material and the friction coefficient of the mat material surface were evaluated. . Table 2 shows the results in each example. In addition, in Table 2, the result of Comparative Examples 1 and 2 is also shown as a reference.

As a result, in the mat material manufactured in Examples 6-10, the interlayer strength of the whole mat material could be made higher than the mat material manufactured in Comparative Examples 1 and 2. Therefore, in the silencer using the mat material manufactured in Examples 6-10 which have such a structure, it is thought that the inorganic fiber peels little by the stress accompanying the flow of exhaust gas. Therefore, it is thought that the damage of the mat material by wind-weather can be prevented efficiently.

Moreover, in the mat material manufactured in Examples 6-10, the friction coefficient of the 2nd surface especially in the surface of the mat material could be made lower than the mat material manufactured in Comparative Examples 1 and 2. Therefore, the mat material which was more excellent in handleability was made.

And in the mat material manufactured in Examples 6-10, it was possible to set it as the mat material from which the density of inorganic fiber bundle formation differs on the 1st surface and the 2nd surface.

When manufacturing a silencer using the mat | matte material of Examples 6-10, the 2nd surface with many inorganic fiber bundles is arrange | positioned at the outer pipe side (outer side), and the 1st surface with few inorganic fiber bundles is provided at the inner pipe side. It can arrange in (inner side).

Therefore, in the silencers of Examples 6 to 10 manufactured by using the mat members of Examples 6 to 10, the cases of the inorganic fibers being peeled off by the stress accompanying the flow of the exhaust gas are the mats prepared in Comparative Examples 1 and 2. It is thought to be much less than ash. Therefore, it is thought that the damage of the mat material by wind-weather can be prevented very efficiently.

(Other Embodiments)

In the mat member of the present invention, the formation density of the second inorganic fiber bundle formed on the first surface and the formation density of the first inorganic fiber bundle formed on the second surface may be the same. In such a mat material, (1)-(13) can be exhibited among the effect of the mat material of this invention mentioned above.

The size of the mat member of the present invention is not particularly limited because it is determined by the sizes of the inner pipe and the outer pipe used in the muffler of the present invention, but when used in the muffler, a gap between the side of the inner pipe and the outer pipe is used. It is preferable to have a magnitude | size which does not form. This is because in the state where the gap is formed between the side surface of the inner pipe and the outer pipe, the temperature of the portion where the gap of the outer pipe is formed increases, discoloration by heat occurs, and the appearance of the outer pipe is damaged.

In the inorganic fiber which comprises the mat material of this invention, it is not limited to the inorganic fiber containing the alumina and silica mentioned above, The inorganic fiber containing another inorganic compound may be sufficient.

Moreover, the inorganic fiber containing only alumina in alumina and a silica may be sufficient, and the inorganic fiber containing only silica may be sufficient.

A composition ratio of the inorganic fibers containing alumina and silica, in a weight _{ratio, Al 2 O 3: SiO 2} = 60: 40 ~ 80: 20 is preferable, _{and, Al 2 O 3: SiO 2} = 70: 30 ~ 74: It is more preferable that it is 26.

In the inorganic fibers containing only alumina of alumina and silica, in addition to alumina, for example, it may contain an additive such as CaO, MgO, ZrO _2.

In the inorganic fibers containing only silica of alumina and silica, other than silica, for instance, it may contain an additive such as CaO, MgO, ZrO _2.

It is preferable that it is 250 micrometers or more, and, as for the average fiber length of the inorganic fiber which comprises the mat material of this invention, it is more preferable that it is 500 micrometers or more. When the average fiber length is less than 250 µm, the fiber length of the inorganic fibers constituting the mat material is too short, and the interlayer strength of the entire mat material is lowered.

In addition, the upper limit of the average fiber length of an inorganic fiber is not specifically limited, since the spun inorganic fiber precursor is obtained in the continuous state.

The shape of the concave portion and the convex portion formed on the long side of the mat member of the present invention is not particularly limited as long as the concave portion and the convex portion are fitted to each other. It is preferable that the convex part which protruded over the magnitude | size of x length 10mm-width 80mm x length 200mm is formed, and the recessed part of the shape fitted to it is formed in a part of the other long side. When manufacturing a silencer using the mat material which has the shape of such a recessed part and a convex part, since a mat material can be reliably wound to an inner pipe, handling property becomes excellent.

Moreover, the some side part and the convex part which fit together may be formed in the long side of the said mat material, and the recessed part and the convex part do not need to be formed.

In the mat member of the present invention, the size of the inorganic fiber bundle formed on the needle traces is not particularly limited because it is determined according to the shape of the needle, but is preferably 0.5 to 10.0 mm in diameter. It is because the friction force between the surface of a mat material and the inner surface of an outer pipe can be reduced more when a silencer is manufactured using the mat material of this invention as the magnitude | size of an inorganic fiber bundle is the said range.

It is preferable that the quantity of the organic binder contained in the mat member of this invention is 0.5-12.0 weight%, It is more preferable that it is 0.5-5.0 weight%, It is further more preferable that it is 0.5-1.0 weight%. If the amount of the organic binder is less than 0.5% by weight, the inorganic fibers are hardly adhered to each other, so that dropping of the inorganic fibers constituting the mat member easily occurs. On the other hand, when the amount of the organic binder exceeds 12.0% by weight, when used as a silencer, the amount of organic components discharged from the silencer is increased, so that a load is applied to the environment.

Although the weight per unit area of the mat member of this invention is not specifically limited, It is preferable that it is 900-3000 g / m <2>, and it is more preferable that it is 1500-2800 g / m <2>.

Although the thickness of the mat member of this invention is not specifically limited, It is preferable that it is 6-31 mm, and it is more preferable that it is 9-20 mm.

In the manufacturing method of the mat member of the present invention, as for the shape of the barb used for forming the entanglement of the inorganic fiber and the inorganic fiber bundle, the needle as described above can be formed if the entanglement of the inorganic fiber and the inorganic fiber bundle can be formed. It is not limited to the shape which protruded toward the front-end direction of, For example, the shape which protruded toward the bottom direction of the needle may be sufficient.

In this case, since the inorganic fiber precursor is not attracted to the barb in the process of injecting the needle into the sheet-like material, the bundle-shaped inorganic fiber precursor is not formed in the needle ejection trace. On the contrary, since the inorganic fiber precursor is attracted to the barb during the needle extraction process, the bundle-shaped inorganic fiber precursor is formed on the needle penetration mark. Therefore, when the sheet material is fired, an inorganic fiber bundle is formed on the surface on which the needle penetration traces are formed, and a mat material in which the inorganic fiber bundle is not formed on the surface on which the needle penetration traces are formed can be obtained.

In the manufacturing method of the mat material of this invention, as an inorganic compound contained in the liquid mixture (spinning mixture) for manufacturing an inorganic fiber precursor (an inorganic fiber precursor which becomes an inorganic fiber containing alumina (alumina and silica) after baking). It is not limited to the basic aluminum chloride mentioned above, What is necessary is just the inorganic compound used as an alumina after baking. As an inorganic compound which turns into alumina after baking, basic aluminum acetate, aluminum oxychloride, etc. are mentioned, for example.

In addition, when preparing inorganic fibers containing silica (alumina and silica), an inorganic compound which becomes silica after firing is used. Examples of the inorganic compound include silica sol, tetraethyl silicate, and water-soluble siloxane derivative. Can be mentioned.

When producing an inorganic fiber containing alumina and silica, for example, basic aluminum chloride so that the composition ratio in the inorganic fiber after firing is Al ₂ O ₃ : SiO ₂ = 60: 40 to 80:20 (weight ratio). It is preferable to mix | blend a silica sol with aqueous solution. In particular, the composition ratio of the inorganic fibers after firing _{Al 2 O 3: SiO 2 =} 70: 30 ~ 74: It is more preferable to compound a silica sol to a basic aluminum chloride aqueous solution to be 26.

Although it does not specifically limit as an organic polymer added to the said liquid mixture (spinning mixture), In addition to the above-mentioned polyvinyl alcohol, polyethylene oxide, hydroxyethyl cellulose, hydroxymethyl cellulose, carboxymethyl cellulose, polyethylene glycol, sodium polyacrylate Water-soluble organic polymers, such as these, are mentioned.

In the manufacturing method of the mat material of this invention, it is preferable that the liquid amount of the spinning mixture extruded from the spinning mixture supply nozzle by the blowing method is about 3-50 ml / h. Under these conditions, the spinning solution extruded from the spinning solution supply nozzle does not become a spray (fog) and is sufficiently stretched, and the inorganic fiber precursors are not easily welded to each other. Therefore, a uniform inorganic fiber precursor having a narrow fiber diameter distribution (inorganic fiber) Can be obtained.

In the manufacturing method of the mat member of the present invention, in the case of manufacturing a mat member having a different density of formation of the second inorganic fiber bundle formed on the first surface and the first inorganic fiber bundle formed on the second surface, the densities of the needles described above are different from each other. In addition to the method of using two needle boards attached to each other, two needle boards having the same formation density of the needles may be used, and the number of needle punching treatments may be changed.

Moreover, in the manufacturing method of the mat material of this invention, when manufacturing the mat material in which the formation density of the 2nd inorganic fiber bundle formed in the 1st surface and the 1st inorganic fiber bundle formed in the 2nd surface is the same, it implements as follows. You may also

First, two needle boards on which needles are mounted at the same density with each other are prepared, and each needle board is spaced apart from the first or second surface of the sheet-like article. At this time, in the needle punching process, the needle boards are arranged so that the needles formed on the respective needle boards do not collide, but are alternately combined.

Next, the needle punching process is performed by simultaneously moving each needle board up and down along the thickness direction of a sheet-like thing, and a needle punching process body is produced. In this case, the needles pass through the barb formed on the tip portion of the needle with respect to both sides of the sheet-like article until it completely comes out on the opposite surface of the sheet-like article.

By performing each process with respect to the obtained needle punching processed body similarly to 1st Embodiment, the mat material in which the formation density of the 2nd inorganic fiber bundle formed in the 1st surface and the 1st inorganic fiber bundle formed in the 2nd surface is the same is obtained. It can manufacture.

In the manufacturing method of the mat member of this invention, as an organic binder contained in the organic binder solution impregnated in a cut sheet form, it is not limited to the above-mentioned acrylic resin, For example, rubber, such as acrylic rubber, carboxymethylcellulose, or Water-soluble organic polymers such as polyvinyl alcohol, thermoplastic resins such as styrene resins, and thermosetting resins such as epoxy resins. Among these, acrylic rubber, acrylonitrile-butadiene rubber and styrene-butadiene rubber are particularly preferable.

The organic binder solution may contain a plurality of types of organic binders described above.

The organic binder solution may be a solution obtained by dissolving the above-described organic binder in water or an organic solvent, in addition to the latex obtained by dispersing the above-described organic binder in water.

In the manufacturing method of the mat member of this invention, when pressure-drying an impregnation sheet-like thing, it is preferable to dry at the temperature of 95-155 degreeC. If the said temperature is less than 95 degreeC, drying time will become long and a production efficiency will fall. Moreover, when the said temperature exceeds 155 degreeC, an organic binder will decompose | disassemble and it will become impossible to adhere | attach the inorganic fibers which comprise a mat material, and the fall of an inorganic fiber will arise.

Moreover, in the manufacturing method of the mat | matte material of this invention, as a method of manufacturing the inorganic fiber from which an average fiber diameter differs, it is a spinning method in a blowing method, for example, changing the flow velocity of the gas flow injected from an air nozzle. The method of manufacturing the inorganic fiber precursor which has an average fiber diameter substantially the same as the said range by changing the conditions which spin a mixture, etc. are mentioned.

When changing the flow velocity of the gas stream injected from an air nozzle, and producing inorganic fiber from which an average fiber diameter differs, it is preferable that the gas flow rate injected from an air nozzle is 40-200 m / s. Moreover, it is preferable that the diameter of a spinning mixture supply nozzle is 0.1-0.5 mm, and it is preferable that the liquid amount of the spinning mixture extruded from a spinning mixture supply nozzle is 1-120 ml / h.

In the silencer of the present invention, a plurality of mat members may be wound in a multi-layered form on the side of the inner pipe, and in this case, the length of each mat member may be as long as the mat member located on the outer pipe side. In the case of manufacturing the silencer having such a configuration, after the mat member is wound on the side surface of the inner pipe, the mat member is repeatedly wound on the mat member again to repeat the process of winding the mat member. What is necessary is just to manufacture the inner pipe wound by the process, and to manufacture a silencer similarly to 1st Embodiment using this inner pipe.

Moreover, it is preferable that the mat material arrange | positioned at the inner pipe side of a silencer among the said some mat material consists of a material with high heat resistance. This is because a high temperature resistance is required for the mat member disposed on the inner pipe side since the temperature of the inner pipe becomes high due to the introduction of a high temperature exhaust gas. Specifically, it is preferable that the inorganic fiber mainly contains alumina, silica, or the like.

On the other hand, the mat member disposed on the outer pipe side whose temperature is lower than the inner pipe does not require high heat resistance compared to the mat member disposed on the inner pipe side. Therefore, the mat member disposed on the outer pipe side may be formed of a material having lower heat resistance than the inorganic fiber described above. It is preferable that it mainly consists of glass fiber etc. specifically ,.

Further, in the silencer, one mat member may be wound spirally on the side of the inner pipe. In this case, the shape of the mat member is sufficiently smaller than the length of the inner pipe, and the length is the number of times the mat member is wound. It is sufficient to have an elongated flat plate of substantially rectangular shape in plan view, which is approximately equal to the length of the outer circumference of the inner pipe.

In the case of manufacturing such a muffler, the mat member of the above-described shape is wound in a spiral shape so that the mat members do not overlap the side surfaces of the inner pipe, and the silencer is manufactured in the same manner as in the first embodiment using the inner pipe. Just do it.

In the silencer of the present invention, the length of the inner pipe may be approximately equal to the size of the sum of the length of the outer pipe and the thickness of the end member disposed at both ends of the outer pipe. In this case, in the silencer 70 of the first embodiment shown in Figs. 4 (a) and 4 (b), a shape in which both ends of the inner pipe 73 do not protrude from the end face of the end member 73 is formed. do.

FIG. 1 (a) is a partially cutaway perspective view schematically showing a mat member including a cross section obtained when an example of the mat member of the present invention is cut along the thickness direction, and FIG. 1 (b) is a diagram. It is a perspective view which showed typically the inorganic fiber bundle formed in the surface of the mat material shown to 1 (a).

FIG. 2: (a) is a perspective view which shows typically the state observed from one surface side about an example of the mat material of this invention, FIG. 2 (b) is the mat shown to FIG. 2 (a) It is a perspective view which shows typically the state which observed the ash from the other surface side.

3 is an optical photomicrograph of an inorganic fiber bundle formed on a needle bleed trace on the surface of a mat member of the present invention.

4: (a) is a perspective view which shows an example of the silencer of this invention typically, and FIG. 4 (b) is sectional drawing A-A line of the silencer shown to FIG. 4 (a).

5 (a), 5 (b), 5 (c), and 5 (d) each show a mat member, an inner pipe, an outer pipe, and a stage constituting the silencer of the present embodiment in order. It is a perspective view which shows an example of an bouillon member typically.

FIG. 6: is a perspective view which shows typically the form which manufactures a silencer using the inner pipe, mat material, outer pipe, and end member shown to FIG. 5 (a)-(d). FIG.

FIG. 7: (a) is explanatory drawing of the interlayer strength measuring apparatus, and FIG. 7 (b) is a perspective view which shows typically the shape of the sample for interlayer strength measurement.

8 is an explanatory diagram of a friction coefficient measuring device.

FIG. 9: (a) is a perspective view which shows typically the state observed from one surface side regarding an example of the mat material of this invention, FIG. 9 (b) is the mat shown to FIG. 9 (a). It is a perspective view which shows typically the state which observed the ash from the other surface side. FIG. 9 (c) is a cross-sectional view taken along a line D-D schematically illustrating a cross section obtained by cutting the mat member shown in FIG. 9 (a) in a direction perpendicular to the longitudinal direction.

(Explanation of the sign)

10, 100: Matte

13a, 13b: surface

14: needle penetration

15: needle trace

16: needle marks

18, 18a, 18b, 18c, 18d, 18e: inorganic fiber bundle

70: silencer

71: outer pipe

72: end member

73: inner pipe

74: pore

113a: first surface

113b: the second surface

114a: First Needle Intrusion Mark

115a: first needle trace

116a: first needle trace

118a: first inorganic fiber bundle

114b: second needle penetration

115b: 2nd needle outflow trace

116b: Second needle mark

118b: second inorganic fiber bundle

Claims (9)

A mat material for a silencer wound around an inner pipe in which small pores are formed, and disposed to be formed inside the outer pipe, The mat material for silencer is formed by a needle punching process containing inorganic fibers and advancing from a needle penetration mark formed on the surface to a needle penetration mark formed on a surface opposite to the surface on which the needle penetration mark is formed. With multiple needle traces, In the needle bleed trace, an inorganic fiber bundle in which a plurality of the inorganic fibers are oriented in a closed loop shape is formed, The inorganic fiber bundle is formed on at least one surface, A surface of the inorganic fiber bundle is formed, the mat member for silencer, characterized in that disposed on the outer pipe side. The method of claim 1, The needle trace is a first needle trace which advances from the first needle penetration mark formed on the first surface of the mat member to the first needle penetration mark formed on the second surface, A silencer mat member comprising: a second needle trace extending from a second needle penetration trace formed on the second surface of the mat member to a second needle penetration trace formed on the first surface. The method of claim 2, The formation density of the 2nd inorganic fiber bundle formed in the 1st surface of the said mat material, and the formation density of the 1st inorganic fiber bundle formed in the 2nd surface of the said mat material are different, The silencer mat material characterized by the above-mentioned. The method according to any one of claims 1 to 3, Silencer mat material, characterized in that the average diameter of the inorganic fiber is 3 ~ 10 ㎛. The method according to any one of claims 1 to 3, Formation density of the needle trace is 7 ~ 30 pieces / ㎠ The mat material for silencer. The method according to any one of claims 1 to 3, The inorganic fiber is a silencer mat material, characterized in that the inorganic fiber containing at least one of alumina and silica. The method according to any one of claims 1 to 3, Mat material for silencer comprising an organic binder. Internal pipes with small pores, Mat material for the silencer wound around the inner pipe, A silencer provided in an exhaust path of an internal combustion engine, comprising an outer pipe in which an inner pipe on which the mat material for the silencer is wound is disposed, and an end member formed in both ends of the outer pipe. The mat material for silencer is formed by a needle punching process containing inorganic fibers and advancing from a needle penetration mark formed on the surface to a needle penetration mark formed on a surface opposite to the surface on which the needle penetration mark is formed. With multiple needle traces, In the needle bleed trace, an inorganic fiber bundle in which a plurality of the inorganic fibers are oriented in a closed loop shape is formed, The inorganic fiber bundle is formed on at least one surface, The silencer characterized in that the surface on which the inorganic fiber bundle is formed is disposed on the outer pipe side. Winding process of winding the mat material for silencer on the inner pipe in which the pore was formed, A press-fitting manufacturing step of manufacturing a press-fitting body by press-fitting the inner pipe wound with the silencer mat material inside the outer pipe, A method of manufacturing a silencer, in which an end member is disposed at both ends of an outer pipe of the indented body, and then a fixing step of fixing the end member and the outer pipe of the indented body is performed. The mat material for silencer contains an inorganic fiber, and is formed by a needle punching process that extends from a needle penetration mark formed on a surface to a needle penetration mark formed on a surface opposite to the surface on which the needle penetration mark is formed. With the needle mark, In the needle bleed trace, an inorganic fiber bundle in which a plurality of the inorganic fibers are oriented in a closed loop shape is formed, The inorganic fiber bundle is formed on at least one surface, And a surface of the silencer mat member on which the inorganic fiber bundle is formed is disposed on the outer pipe side to wind the silencer mat member on the inner pipe.

Images